Dated tax article includes it (5)
I believe the answer is:
tithe
'dated tax' is the definition.
'tithe' can be an answer for 'tax' (historical tax paid to the church). I'm not certain of the 'dated' bit.
'article includes it' is the wordplay.
'article' becomes 'the' (the definite article).
'includes' indicates putting letters inside.
'the' going around 'it' is 'TITHE'.
Can you help me to learn more?
(Other definitions for tithe that I've seen before include "Levy, originally worth one tenth" , "Tax to support the church" , "financial contribution" , "Source of church revenue" , "Levy by church, e.g." .)